(a) Field
The invention relates to a liquid crystal display and a method of manufacturing the same.
(b) Description of the Related Art
A liquid crystal display is one of the most common types of flat panel displays. The liquid crystal display includes two display panels on which electrodes are disposed, and a liquid crystal layer interposed therebetween. The liquid crystal display controls the intensity of transmitted light by rearranging liquid crystal molecules of the liquid crystal layer by applying the voltage to the electrodes.
Among the flat panel displays, the liquid crystal display generally has various structures in which field generating electrodes are provided in two display panels, respectively. Among the structures, one mainstream structure is a structure where a plurality of thin film transistors and pixel electrodes are arranged in a matrix form in one display panel (hereinafter, referred to as ‘thin film transistor array panel’), color filters of red, green and blue are disposed in the other display panel (hereinafter, referred to as ‘common electrode panel’), and a common electrode covers the entire surface thereof.
However, in such a liquid crystal display, since the pixel electrodes and the color filters are on different display panels, precisely aligning the pixel electrodes and the color filters may be difficult, and thus, an alignment error may occur. A structure such as a color filter on array (“COA”) where the color filters and the pixel electrodes are disposed on the same display panel has been proposed to solve the problem.
Further, considering a bonding margin when the thin film transistor array panel and the common electrode panel are bonded, a light blocking member such as a black matrix should be manufactured to be larger than a miminal size. However, since an aperture ratio of the liquid crystal display may be deteriorated by the increased size of the black matrix, the black matrix may be disposed in the thin film transistor array panel.
A gap between the two display panels is called a cell gap, and the cell gap affects general operation characteristics of the liquid crystal display, such as a response speed, a contrast ratio, a viewing angle and luminance uniformity. If the cell gap is not constant, a uniform image is not displayed over an entire screen of the liquid crystal display causing undesirable defects in image quality. Therefore, a plurality of spacers are disposed on one side of the two display panels in order to maintain the uniform cell gap over the entire region of the two display panels.
A plurality of spacers may include a main column spacer substantially supporting the two display panels, and a sub-column spacer assisting the main column spacer.
In manufacturing a liquid crystal display, the light blocking member such as the black matrix, and the spacers, may be simultaneously formed in order to simplify a manufacturing process. Multiple processes are implemented in order to simultaneously form the light blocking member, the main column spacer, the sub-column spacer and the like.
In the multiple processes, a mask that can implement multiple transmittance areas and a material that facilitates the multiple processes are used. However, the multiple transmittance mask and corresponding material are limited. Therefore, there exists a need for an improved mask and/or material in the process of simultaneously forming light blocking and spacer elements of the liquid crystal display.